Malicious PDF — malware analysis report

Static analysis result for SHA-256 1ced586393ebcff4…

MALICIOUS

PDF

75.6 KB Created: 2021-09-29 01:53:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4f3e4bc2aa46473182bb58ba607b84ae SHA-1: 44657b6d2ead50b7b1d417dcd4e2cf961faa45b5 SHA-256: 1ced586393ebcff47a2c8d46d885dbd52a832869b66dfafd9ad6115d1249e9ef
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics indicate the PDF contains a link farm pointing to compromised WordPress upload storage and other disposable hosting, suggesting a phishing or malware distribution lure. The embedded URLs and the nature of the heuristics point towards an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9927

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://apartmani-mestrovic-krk.hr/files/84146251173.pdf
    • http://www.reroofingbrisbaneqld.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1612ee445724e5---10237195273.pdf
    • https://mannerfeltdesignteam.se/ckfinder/userfiles/files/93294197691.pdf
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614d7c050e861---watizafuzop.pdf
    • https://doctmcooper.com/userfiles/files/fotitutofedilifewukago.pdf
    • http://asvpp.fr/pdf/widomuluzalenolowiwuki.pdf
    • https://navoloki.mebel18.com/uploads/files/kukux.pdf
    • https://fullhousetourism.com/UploadFiles/file/20210917194708185.pdf
    • https://gberwanda.com/gbe/useruploads/blogs/files/burazujexixu.pdf
    • https://kenhquangcao.vn/uploads/files/49662979612.pdf
    • http://yunnanyingxiang.com/ckfinder/userfiles/files/38082669458.pdf
    • http://benetalent.com/upload/files/bowenunadekinosanedunoni.pdf
    • http://aedjtj.pretty-match.com/upload/files/kanozanibejiregi.pdf
    • http://hodoan.net/userfiles/file/27111389988.pdf
    • http://life-homeshop.buyout8.com/asset/uploads/files/xetofapox.pdf
    • http://global-poseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/16149196dda6d2---wodopuf.pdf
    • http://siblom.ru/files/upload/file/80659469031.pdf
    • https://kildevangen.dk/files/80112387933.pdf
    • http://nhakhoasaigonkimcuong.com/uploads/images/files/91282087815.pdf
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614cd93f2688b---wumifatinof.pdf
    • http://tecnoservizi.com/userfiles/files/napufowuri.pdf
    • https://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16136759d66362---ritev.pdf
    • http://currycornersugarland.com/admin/images/file/risokatapelovofokiwogi.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=mortal+kombat+movie+2017
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_005_off000107ed.bin
735135a7a26790fd7c74f66bc6d7b7c5356276db534ddc6e6595877d953b97c4
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x107ED 16888 bytes
font_00_sfnt_off0000b035.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB035 16792 bytes
font_01_sfnt_off0000c84c.bin
79a14db5e12151f976ef20e7948ddd844ec84b4b54f99675cde1c82ec8416685
pdf-font-stream PDF embedded font (sfnt) at offset 0xC84C 10632 bytes
font_02_sfnt_off0000e0d0.bin
a6f300b23f9bb4f958fc7a6da4d7cec841f6909bef6860b53b4bfe7aaa5b6127
pdf-font-stream PDF embedded font (sfnt) at offset 0xE0D0 15336 bytes